Method of deriving hydrazobenzol and its homologues



UNITED ,STATES PATIENT OFFICE.

WILLIAM H. MAHLER, OF NEWARK, NEW JERSEY.

inmon or nmtivme EYDRAZOBENZOL AND ms noimonoeuns.

Ito Drawing.

To all whom it may concern:

Be it known that I, WILLIAM H. MAHLER, a citizen of the United States of America, re-

sidin at Newark, county of Essex, State of 98 New ersey, have invented certain new and useful Improvements in Methods of Deriving Hydrazobenzol and Its. Homologues, of which the followin is a Specification.

The invention re ates to a method. of deriving hydrazobenzol, hydrazotoluol and other homologues.

More particularly, the invention relates to the method of deriving hydrazobenzol, hydrazotoluol' and other homologues .by the hydrogenation or reduction of mtrobenzol or corresponding homologue by the use of zinc in particle form, such as zinc flakes, granules or feathers. Caustic soda, or equivalent, is employed in. reaction with the granular, flaked or feather zinc to produce the nascent hydrogen.

The proportional parts of nitrobenzol and the reacting agents may be ascertained by y the following example:

123 lbs. nitrobenzol,

200 lbs. zinc granules, 50% lbs. caustic soda, with about 300 lbs. of water.

In carrying out my invention, the full'zinc flakes or feathers,

content is charged with the remainder of the charge into a suitable reducer and subjected to thorough agitation. Preferably, the reducer is constructed in accordance with the features disclosed in my co-pendin application Serial Number 236,512, filed ay 25, 1918, entitled Chemical apparatus, and comprising a rotatable drum, mounted on suitable'bearings, and provided interiorly with spaced shelves disposed radially on the inner surface of the drum and open-faced spaced agitation members extendmg between the shelves and the axis of the drum and stag-.

gered relatively to one another.

The proper quantity of water is first charged in the charglng opening ofthe drum, then the caustic soda is added, then the nitrobenzol and finally the full content of the zinc in granular, flake or feather form. Preferably, the zinc particles are equally distributed on the bottom face of the drum.

' The closure of the charging opening is.

then sealed and the'drum rotated under suitable power from 15 to 20revolutions per minute, untilthe reactidn has been completed, covering a period of from fourteen to eighteen hours.

Specification of Letters Patent.

Application filed May 25,

Patented. Feb. 7, 1922.

1 918. Seria1No. 236,511.

.The resulting evolution of the nascent hydrogen generates its own reaction temperature, approximately a maximum of O Preferably, the drum is enclosed with an asbestos coating to minimize the dissipation of the evolved heat. The drum and its mounting means are preferably also-enclosed in a wooden housing or similar structure of heat-insulating material."

The termination stage of the reaction is indicated by a fall in temperature, of say below 50? (l, shown by a pyrometer indicator card, or equivalent.

Upon sealing the closure after charging and rotating the drum, no attention whatsoever is required; mere inspectionof the temperature indicator will indicate when the final stage has been reached.

The evolved gases are discharged through a suitable piping, xtending through a trunnion of the drum.

My invention obviates the necessity obtaining in heretofore proposed methods of continuously supplying the zinc in the form of dust by an operator throughout the period of the reaction, resultin in a high proportion of loss of the zinc net and loss in heat energy.

- The invention is highl advantageous in making possible the use 0 the cheaper form of zincmetal. 4 p a M invention is especiall beneficial to man ind in avoiding the impairment of health and serious sickness, often resulting in death, due to the dissemination of the zinc dust in the atmosphere.

Further advantages of my invention reside in effecting a uniform distribution of the zinc, with attendant uniform liberation of the nascent hydrogen; also in obviating the need of steam or other endothermic means. 4

"The hydrazobenzol is separated from the accompanying reaction products of the the expression zinc in the form of individual particles each having a relatively large mass and a relatively small surface area to gefine the same from zinc in the form of ust.

Whereas I have described my invention by reference to specific ingredients and proportional .parts thereof, it will be understood that the same maybe varied or modified without departing from the invention as defined by the appended claims.

I claim. -1. The method of deriving hydrazobenzol, comprising subjecting an aqueous mixture of nitrobenzol and caustic soda to the action of zinc in the form of particles having a large mass and a small surface area as compared with filings, the full charge of nitrohenzol caustic soda, and zinc being located at one time and discharging the evolved gases.

2. The method of deriving hydrazobenzol, comprising charging a mixture of Water, nitrobenzol, caustic soda and the entire required amount of zinc in the form of particles, each particle being of large mass and having a small surface area as compared with filings and discharging the evolved gases.

In testimony whereof I have signed this specification this 23rd day of Ma 1918. v

WILLIAM H. HLER. 

